NEAR Smart Contracts · 1 min read

Setup and Tooling

Install Rust, the Wasm target, cargo-near, and near-cli-rs, then build a contract without touching testnet yet.

You will write contracts in Rust or JavaScript, compile them to WebAssembly, and talk to testnet with a CLI. Official docs live at docs.near.org.

Install the toolchain

bash

# Rust + the Wasm target
curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
rustup target add wasm32-unknown-unknown
 
# cargo-near (build and deploy helpers)
curl --proto '=https' --tlsv1.2 -LsSf \
  https://github.com/near/cargo-near/releases/latest/download/cargo-near-installer.sh | sh
 
# near-cli-rs (the `near` command)
curl --proto '=https' --tlsv1.2 -LsSf \
  https://github.com/near/near-cli-rs/releases/latest/download/near-cli-rs-installer.sh | sh
# or: npm install -g near-cli-rs@latest

Create a project with cargo near new hello (Rust) or the JS project generator in the docs. near defaults to testnet. Pass --networkId testnet anyway so the command is explicit.

A first build

bash

cargo near build non-reproducible-wasm
# Wasm lands in ./target/near/<crate>.wasm

You do not need a testnet account until the deploying lesson. Until then, cargo test runs on your machine.

What you will use later

Tool	Job
`cargo near build`	Compile the contract to Wasm
`cargo test`	Unit and sandbox tests
`near create-account ... --useFaucet`	A free testnet account
`near deploy` / `cargo near deploy`	Put Wasm on that account
`near view` / `near call`	Read and write methods

The older Node near-cli package is not what current docs recommend. Use near-cli-rs.

Exercise

Install the tools on your machine (or note which ones you still need). Run near --version and cargo near --version and keep the output. You will deploy in the last lesson.

Open in Playground

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Overview Writing and Testing a Contract